Pipe-threading die.



No. 784,568. PATENTED MAR. 14, 1905.

H JANSEN.

PIPE THREADING DIE.

AAAAAAAAAAA FILED JUNE 17, 1904.,

UNITED STATES Patented March 14, 1905.

PATENT OFFICE.

HENRY JANSEN, OF CHICAGO, ILLINOIS, ASSIGNOR TO THE NYE TOOL AND MACHINE \VORKS, A CORPORATION OF ILLINOIS.

PlPE-THREADING DIE.

SPECIFICATION forming part of Letters Patent No. 784,568, dated March 14, 1905.

Application filed June 17, 1904. Serial No. 212,947.

To all whom it may concern:

Be it known that I, HENRY JANsEN, a citizen of the United States of America, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Pipe-ThreadingDies, of which the following is a specification.

The present invention relates to that class of screw-cutting dies employed in trimming, tapering, and threading the ends of metal pipes, &c., andhas for its object to provide a structural formation and arrangement of the die parts by means of which the formation of a taper-thread upon the end of a section of pipe is effected in a uniform, rapid, and efficient manner with the expenditure of a minimum amount of force and with which undue or excessive stress upon any of the cutting edges of the die during the operation is avoided, with a consequent durability and efliciency in such cutting edges during long-continued use, all as will hereinafter more fully appear, and be more particularly pointed out in the claims. 1

In the accompanying drawings, Figure 1 is a front elevation of a pipe-threading die embodying the present invention. Fig. 2 is a transverse section at line a: :1, Fig. I, with the end of the pipe in position at the beginning of the tapering and threading operation.

Fig. 3 is a similar view illustrating the completion of the tapering and threading operation on the end of the pipe. Fig. I is an enlarged fragmentary section of the lower portion of the die and pipe shown in Fig. 3. Fig. 5 isan enlar ed fragmentary transverse section at line at a", Fig. I.

Similar numerals of reference indicate like parts in the several views.

Referring to the drawings, 1 represents the body portion of the die of a rectangular or other usual form and having a central bore provided with a series of four or more instanding blades 2, 3, 4:, and 5 integral with the body portion of the die and arranged in pairs having opposed relation to each other at opposite sides of the longitudinal axis of such bore, as usual in the present type of dies. In the present improvement one opposed pair 2 and 3 of the instanding blades extend the length of the die-bore with their cutting-faces inclined toward each other, so as to impart the required tapering end to the section of pipe operated upon, and each blade is provided with a series of threading-teeth 6 and intermediate planing edges 7 Each of such planing edges extends from the base of one threading-tooth to the base of the next adjacent threading-tooth, and the formation is such that each planing edge 7 is substantially equal in extent to the base of a threadingtooth 6, with the threading-teeth and planing edges of one instanding die-blade in staggered or alternated relation to the corresponding threading-teeth and planing edges of the opposed instanding die-blade 3, as illustrated in Figs. 2 and 3, and so that in the rotation and normal forward feed of the die in use the planing edges of the one instanding blade will operate in paths which had been previously traversed by the threading-teeth of the other instanding blade, and vice versa, and as hereinafter more fully set forth in the operation of the die. The other or companion pair of instandingdie-blades 4 and 5 are each provided with a single full-sized threading-tooth 8 near the front of the die and immediately to the rear of the usual countersunk die-entrance, the remainder of said die-blades 4 and 5 being cut away, as shown in Fig. 5, for the purpose hereinafter more fully set forth. The thread-.

ing-teeth 8 are arranged on a common pitchline with the first or forward threading-teeth of the other instanding die-blades 2 and 3 and as so arranged provide a construction in which there is a full threading-tooth on all of the instanding die-blad es immediately back of the usual countersunk die-entrance. Following such arrangement of the first or forward threading-teeth just described the alternating and staggered arrangement is made in the threading-teeth and planing edges 7 of the dieblades 2 and 3, as heretofore set forth.

Extended practical experiment has shown that the above-described provisions of a full threading-tooth arranged on a common pitch at the forward end of all the instanding dieblades is an absolute requisite in order to prop erly and readily start the die and that without such equivalent provision it is next to impossible to start a taper threading-die. Such experiment has also shown that a single threadingtooth 8 on the respective die-blades 4 and 5 meets all practical requirements and that the remainder of such die-blades can be removed,as above set forth, with a consequent reduction in friction and an increase in clearance in the die during actual use.

The present invention has its greatest practical merit in taper-bore dies adapted to cut taper-threads upon pipes and the like, and the operation of the present die is as follows: In the initial rotation of the die the series of first or forward threading-teeth of the series of instanding die-blades having the described arrangement on a common pitch line are adapted to cut into the metal of the pipe end operated upon to approximately their full depth and are followed by the first planing edges 7 of the instanding blades 2 and 3, which remove the apex of the thread just formed, and so that the work of further reduction of said thread by the succeeding threading-teeth is materially reduced. The remaining series of threading-teeth and planing edges of the instanding blades 2 and 8 are successively brought into action as the operation progresses to repeat the actions above described upon the successive portions of the screw-thread until the operation is completed. As a result of such successive and substantially simultaneous cutting actions of the threading-teeth and planing edges a light out is taken by each threading-tooth or planing edge, so that While rapidity of operation is afforded the stress upon said teeth or edges is comparatively light and in consequence the eifectiveness of the present die is correspondingly extended for a much greater time than is attained by a die having no such uniformity of cutting action.

Having thus fully described my said invention, what 1 claim as new, and desire t0 secure by Letters Patent, is

1. A screw-cutting tool provided with a series of blades formed with threading-teeth,

the first threading-tooth of each blade of the series back of the forward end of the tool being full and on a pitch-line with one another, the remainder of the threading-teeth of said blades being alternately removed, and such remaining threading-teeth of one blade having a staggered or alternated relation to the remaining threading-teeth on the next adjoining blade, substantially as set forth.

2. A screw-cutting tool provided with a series of blades formed with threading-teeth, the first threading-tooth of each blade of the series back of the forward end of the tool being full and on a pitch-line with one another, the remainder of the threading-teeth on two opposed blades being entirely removed, and the remainder of the threading-teeth of two other opposed blades being alternately removed and the remaining teeth arranged so that the threading-teeth on one of said blades will have a staggered or alternated relation with the remaining threading-teeth of the other blade, substantially as set forth.

3. A die for cutting, threads on pipe ends and the like, comprising a die-body having a central orifice formed with an entrance-countersink and provided with a series of instanding die-blades,the first threading-tooth of each blade of the series back of the countersink aforesaid being full and on a pitch-line with one another, the remainder of the threadingteeth of said die-blades being alternately removed and such remaining threading teeth of one die-blade having a staggered or alternated relation to the remaining threading-teeth on the next adjoining die-blade, substantially as set forth.

4. A die for cutting threads on pipe ends and the like, comprising a die-body having a central orifice formed with an entrance-countersink and provided with a series of instanding die-blades, the first th reading-tooth of each blade of the series back of the countersink aforesaid being full and on a pitch-line with one another, the remainder of the threadingte eth on two opposed die-blades being entirely removed, and the remainder of the threadingteeth of two other opposed die-blades being alternately removed and the remaining teeth arranged so that the threading-teeth on one of said blades will have a staggered or alternated relation to the remaining threadingteeth of the other blade, substantially as set forth.

Signed at Chicago, Illinois, this 14th day of June, 1904.

, HENRY J ANSEN. Witnesses:

ROBERT BURNS, M. H. HOLMES. 

